1. Field of the Invention
The present invention generally relates to display technology, and particularly relates to a light guide plate, a backlight module, and a display device.
2. The Related Arts
In a display device, a backlight module is employed to provide sufficient and uniform illumination so that the display device is able to present images correctly. Light guide plate (LGP) is a one of the backlight module's components. A LGP is made of optical-grade acrylic or polycarbonate (PC), and a number of light dots are produced on the LGP by dot printing, injection molding, or hot pressing. The light dots interferes light beams' total reflection inside the LGP so that the light beams exit the LGP from a light emission face. By arranging the light dots into various densities and dimensions, the light emitted from the LGP can be uniformed.
As shown in FIG. 1, an existing backlight module contains the following components: a plastic frame 1, a LGP 2, a number of light emitting diodes (LEDs) 3, and a flexible printed circuit (FPC) 4. Usually the LEDs 3 are welded to pads on the FPC 4 and they can be considered as a single component. As shown in FIG. 2, a number of support elements 11 are configured on the plastic frame 1, and the LEDs 3 are installed between neighboring support elements 11 by adhesion. Additionally, a slope is usually configured at the rims of the LGP 2 so as to reduce the thickness of a major region of the LGP 2. FPC 4 is installed on the LGP 2 also by adhesion to facilitate the LEDs 3's optical coupling a light incident face of the LGP 2.
As the plastic frame 1 is required to be even thinner, the manufacturing of the protruding support elements is getting more difficult, and the stability of the product assembly is also compromised. Additionally, due to the slopes on the LGP, the interface between the LGP and the FPC is reduced to a line of contact. There can easily be relative motion between the LGP and the FPC, causing failure to the optical coupling.